12"CK Headstock Gearing & Oil Pump

In a prior posting, linked below, Tom was inquiring about the volume of oil supplied by the headstock pump.
http://www.practicalmachinist.com/vb/monarch-lathes/12ck-headstock-oil-pump-volume-291622/
Since the pump is cam operated off the bull gear, the volume will change with changes in the bull gear RPM. Notice I said bull gear RPM, not spindle RPM. The bull gear is the same RPM as the spindle when the bull gear is used in the eight lower speeds, but it is not used in the eight higher speeds, but it is still turning, but at a much lower speed, approx 1/7th, of the spindle speed, at least from the calculation I did for shaft C when the shifters were set for the highest speed. For my lathe the bull gear is turning approx 196 RPM, when the spindle is turning 1400 RPM.
I noticed the difference when I investigated this situation in the linked post, but the only way to actually find out what the RPM was to count gear teeth. You can tell I've got a lot to do.
I've taken some pictures and made up a couple charts to illustrate.
The first 4 pictures are of the headstock; the first are the shifters set for the highest speed, the second is an overall view of the HS internals, the third is of the left clutchs, the fourth is of the right hand clutchs. The three left shifters move the clutches in the same dorection as the shifters, the right hand lever moves the clutch in the opposite direction.
The fifth picture is a sketch or the HS gearing with tooth counts. The gears are identified by circled numbers 1-14. The last picture is a chart of the gears used in each speed. If you do the gear calculations, multiply the result by the input RPM, in my case that speed is 1440 RPM.

Oh yes, this still doesn't tell the volume of oil being pumped, just the number of strokes per minute of the pump.

One omission; I cut off the C & D shaft identifiers when I took the picture, sorry about that.












Harry

Interesting. How did you achieve doubling the input speed? Pulleys or high speed motor. An how well does the machine take to the higher speeds? I have heard of increasing the speed 50% to 1100 - 1200 by using a VFD. How big is the motor, 10 Hp?

Oil delivery?

Tom

The lathe was originally 3 HP, I changed the the motor to a 5 HP 1725 RPM, and doubled the the size of the motor sheave. It's a tight fit for the belts at the top of the base casting, not much clearance. I have not had any problems with cutting power. I've had the machine at 1400 once or twice, at 1064 about the same, I just don't like the hot chips bouncing off my arms. In retrospect, if I do this again, I would probably top the machine out at 1000-1200 RPM.
One thing to consider is the fact that the max spindle RPM is less than input RPM, and the motor sheave is smaller than the input sheave.
I'm not sure of the maximum HP Monarch recommended, but I don't think it was over 7-1/2.

Oil Delivery? I'm not quite sure of what you're referring to. If you are referring to the oil pump's ability to work at 196 strokes per minute, I should find out about that Monday or Tuesday. I still haven't closed the HS up, but I'm not expecting any problems.
Harry

One gets a hint of why this design is so great. No sliding gears, just massive dog clutches

Thanks Harry

Here's a picture of the motor sheave. As you can tell there isn't much clearance for the belts, especially on the right side, in fact I had to grind away some of the casting. The sheave is about 8-1/2" D.


The oil delivery question; I finally got the HS cover on and ran the lathe today. At the top speed the oil was doing a drip in the sight glass about every 5-8 seconds. The drips seemed to pick up slightly at the slower speeds. The only reason I can think of is a slight cavitation at the higher speeds. The bull gear and a couple other gears are immersed in the oil sump and picking up the oil and slinging it, lowering the sump oil level. Once the speed is lowered this seems to abate.
Harry

I feel better now that the oil pump in my CK is working correctly. Thank you. Thank you. Thank you.

Tom

Travia

Some trivial information, well maybe not.
Strokes per minute of the pump will match the RPM of the 8 lower speeds. For the 8 higher speeds, the strokes per minute are the same as for speeds 5, 6, 7 & 8 in the 2 blocks of 9, 10, 11, 12, then 13, 14 15, 16.. If you look at the HS gear chart, gears 13 and 14 are not used in the 8 eight higher speeds, but shaft C is still turning, but the compound gear 11-13 are engaged, and 14 is not engaged.

I also have 2 speed errors on the gears used chart; speed 5 which I show as 94 RPM should be 90, and speed 8 shown as 176 should be 196.
Harry